What would happen to my minor child if I died without a Will?

Does your question ask what happens to your assets (i.e., your estate) or to your child himself or herself?  If you are asking about the child (as opposed to the estate), his or her other parent would become the "natural guardian."  If the child does not have another parent, a guardianship proceeding would be required.  You can designate one or more persons to be guardian of your child, and I suggest you do that. If this is a simple matter and you want to designate a close family member, you can find a form for designating a "pre-need guardian" online.  If this is not simple, I strongly suggest you hire a lawyer to prepare this and other documents.

If the other parent is not involved with the child, and you do not want that person to be guardian, you absolutely must prepare legal documents to carry out this intent.  Even with documents, the other parent may gain guardianship if he or she fights for it.  However, you will leave a big mess if you die under these circumstances with no provision for your child. 

If you die without a will in Arizona and you are married, then everything goes to your spouse.  If you are not married and you have a minor child, then everything goes to that child.